Beaver County has better than a 50 percent shot of getting Shell’s gas-fed petrochemical facility built, Gov. Tom Corbett said during a stop at the proposed site on Thursday.

But he still has some big fears.

“I have a fear that the economy could go bad ... and they may say ‘We’re going to wait a year or two,’ ” said Corbett, flanked by several state legislators from the region in front of the zinc plant where Shell hopes to build. “I don’t think any of us want them to wait a year or two.”

Corbett was making his second appearance this summer in the Ohio River communities that could host a new ethane processing plant. A U.S. subsidiary of Royal Dutch Shell plc signed a land deal for the site in Potter and Center — the closing Horsehead Corp. zinc plant — but it has a year or more of planning before officials make a final decision on whether to build, which would take several more years.

Shell is doing financial and environmental assessments before committing, Corbett said, adding that he couldn’t go into further detail because of the state’s confidentiality agreements with the company. Shell officials are probably still evaluating their ability to secure enough ethane from local gas drilling to feed the plant, and the market for that ethane is very competitive, experts and local officials have said.

A Shell spokeswoman said she couldn’t go into a lot of detail about the project or its environmental and technical reviews because of the confidentiality agreements.

“It’s still early in the project, and we don’t have any new updates other than we’re still evaluating the preferred site,” said Kayla Macke, a company spokeswoman in Houston. “There’s nothing that I know of right now that we would ask for, but that could always change because the project’s early. It’s really too soon to tell.”

Lawmakers and community leaders need to keep reinforcing to Shell and the business community that they welcome the plant and are ready to build right away, Corbett and his allies at the event said. It also helps to inform locals who are clamoring for information.

“People want answers and they want to know where we are in the process because it is a generational decision,” said state Rep. Jim Christiana, R-Beaver.

Because the General Assembly approved a tax-free zone in which Shell can build and offered an ethane-use tax credit to subsidize the company with more than $1.6 billion, the Corbett administration told legislators their policy work to help the project is done, said state Rep. Rob Matzie and Sen. Tim Solobay, Democrats who represent parts of Beaver County. That could change if Shell asks for more help, in which case they would have tough decisions to make, they said.

Shell officials have also said they need reassurances of work force training and infrastructure improvements such as fixing a dangerous interchange outside the plant’s entrance, Christiana said. The state increased community college funding this year to help with training and is expecting a public-private partnership, or possibly just private help to fix the interchange, he added.

The state will not have to pay to clean up any environmental contamination on the zinc plant land, Corbett said. That funding will be sorted out between Shell and Horsehead, he said.

One other substantial hurdle the plant could have is an environmental permit, especially for the volatile organic compounds the plant is likely to emit as air pollution. Corbett said he advised the state Department of Environmental Protection to protect the environment, but to work as a partner to Shell — not as an adversary — to get the plant built.